Abstract: Using high-speed camera and Analysator Hannover, three kinds of basic flux-cored wires were tested and analyzed under different welding parameters with rich argon shield gas. The results show that the metal transfer mode was globular repelled transfer with poor arc stability and much spatter under lower welding parameters. With increasing of welding parameters, the metal transfer gradually changed to small droplet transfer and the process became stable. Large granular spatter was caused from the repulsive force acting on the molten droplet and the surface tension of the melt. The long slag column played a guiding role on the metal transfer. Refining the droplet and forming stable and long slag was important to improve the usability of basic flux-cored wire.